Embodiments relate to a light emitting device, a light emitting device package, and a lighting system.
Due to physical and chemical characteristics, group III-V nitride semiconductors are being considered as core materials for light-emitting devices such as light-emitting diodes (LEDs) and laser diodes (LDs). Generally, group III-V nitride semiconductors are formed of a semiconductor material having a compositional formula of InxAlyGa1-x-yN (0≦x≦1, 0≦y≦1, 0≦x+y≦1).
LEDs are a kind of semiconductor device that is used as a light source or used to transmit a signal by converting electricity into infrared rays or light by using the characteristics of compound semiconductors.
Such LEDs or LDs using a nitride semiconductor material are widely used as light-emitting devices. For example, LEDs and LDs are widely used as light sources of various products such as keypad light-emitting units of cellular phones, electric displays, and lighting devices.